Flickr/ Steve Rhodes. Some rights reserved.David Cameron has recently indicated that the RAF sometimes uses drones to kill people who are neither convicted criminals nor members of the armed forces of countries with which Britain is at war. Whatever the status of such actions might be in terms of international law, the question of whether and how such killings might be morally justified arises. John Locke’s theory of a natural right to self-defence might seem to offer a possible answer. However, it gives only limited support to this sort of killing.
Locke argued that all individual human beings have not only a natural moral right to kill those who are a direct threat to themselves but also a natural moral right to kill or punish those who are a threat to other people if there is no legal authority available to fulfil that role.
He went so far as to claim that, if you discover a burglar in your house, it is morally justifiable to kill him even if he has not actually explicitly threatened to kill you yet. The burglar has already indicated ill will by invading your property and privacy. Who knows what else might he do?
Locke considers that it is justifiable ‘… to treat him as one who has put himself into a state of war with me- i.e., kill him if I can; for to that hazard does he justly expose himself whoever introduces a state of war, and is aggressor in it.’ (Second Treatise of Government, paragraph 18)
With general reference to self-defence, Locke writes that it is:
‘… reasonable and just I should have a right to destroy that which threatens me with destruction; for by the fundamental law of Nature, man being to be preserved as much as possible, when all cannot be preserved, the safety of the innocent is to be preferred, and one may destroy a man who makes war upon him, or has discovered an enmity to his being, for the same reason that he may kill a wolf or a lion, because they are not under the ties of the common law of reason, have no other rule but that of force and violence, and so may be treated as a beast of prey, those dangerous and noxious creatures that will be sure to destroy him whenever he falls into their power.’ (Second Treatise of Government, paragraph 16)
This might appear to support, unequivocally, the killing of known terrorists by drones even if it involves- as it often will- the unintended killing of innocent bystanders. However, the matter is more complex than it might initially seem to be.
Locke does not say that we are morally justified in doing anything at all that is required to preserve our lives. He says that we are morally justified in killing someone who threatens to kill us or some other person. Those who can justifiably be killed have placed themselves by their own choice outside the protection of the law of nature by acting contrary to it or, at least, threatening to do so.
For instance, suppose that you were out for a walk and someone appeared from behind a tree holding a gun and threated to shoot you. According to Locke, on the grounds of a natural right to self-defence, you would be justified in shooting and killing that person.
However, suppose that the aggressor held an innocent bystander in front of himself as a shield. Suppose that it were not possible to kill the assailant without killing the bystander or, at least, creating a severe risk of doing so.
Locke does not offer a clear indication of what one ought to do in the face of such a dilemma.
If the innocent person who was being held as a shield also happened to have a gun, it might be thought that he or she would be justified in killing you on the grounds of a right of self-defence.
Manifestly, we would not always, if ever, be justified in shooting innocent pedestrians in such circumstances on the grounds that there might be an armed aggressor hiding behind them.
According to Locke, natural rights are moral rights that all human beings equally hold. If people in Britain are morally justified on the grounds of a natural right to self-defence in taking actions that result – even if unintentionally - in the killing of innocent people in Syria, innocent people in Syria would be similarly justified on the grounds of self-defence in taking pre-emptive and retaliatory strikes against people in Britain even if it led to the deaths of innocent people.
The use of drones to kill people in a non-judicial manner and in a context other than that of war might be morally justifiable. However, it is not clear that Locke’s views on a natural right to self-defence serve particularly well for that purpose especially since drones, like other military weapons, often kill people other than their intended victims. Furthermore, it is the rights and lives of individual human beings as such that Locke considers not the actions, interests or the preservation of states.